Asbestos: Immoral Fibre

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Asbestos Immoral Fibre

• Dr. Mary Louise Hill
• Department of Geology
• Lakehead University

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Asbestos is a commercial name for a group of
minerals that crystallize as long, thin fibres.
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Chrysotile (Mg3Si2O5(OH)4) is a form of
serpentine that occurs in veins of silky fibres.
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Chrysotile has been the most important source of
commercial asbestos because its fibres are
flexible, strong, and can be woven into fabric.
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Certain fibrous varieties of amphibole
(actinolite, amosite, anthophyllite, crocidolite,
tremolite) are also known as asbestos. These
minerals crystallize as straight, sharply pointed
needles.
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• Properties of Asbestos
• Heat resistant
• Incombustible
• Nonconducting
• Chemically inert
• Strong but flexible
• Chrysotile fibres are 8 times stronger than steel
  wire of the same diameter.

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• Uses of Asbestos
• Fireproof clothing
• Brake linings
• Insulation
• Shingles
• Tiles
• Pipes
• Gaskets

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Asbestos, the Magic Mineral

• Inventors creating more and more uses (at peak,
  about 4000 applications)
• Important resource for Canada
• Large asbestos mines in Quebec and Newfoundland

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Serpentine-rich rocks outcrop in the Canadian
Appalachians of Newfoundland and eastern Quebec.
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Geological map of the Thetford Mines ophiolitic
complex.
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Geological map and structural profile of the
Jeffrey Mine in the Asbestos, Quebec area
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Geological map and structural profile of the Lac
Brompton and Mont Orford ophiolitic complexes
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Chrysotile, the fibrous variety of serpentine,
occurs in veins in serpentinite.
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Mining Asbestos
In the past, asbestos was mined from open pit and
underground mines in Newfoundland and Quebec.
Asbestos continues to be mined today in Quebec.
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Asbestos mine in Theford Mines, Que. Photograph
by Pierre Obendrauf, The Montreal Gazette
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Health Hazards of Asbestos
1906 An inspector with the Lady Inspectors of
Factories in Great Britain writes "Of all
injurious dusty processes of which I have again
in 1906 received complaints none I believe
surpass in injuriousness to the workers the
sieving, preparing, carding and spinning
processes in asbestos manufacture." The inspector
also writes that further study is "necessary
before any true idea can be formed of the effect
of this process."
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Known Health Risks of Human Exposure to
Chrysotile Asbestos

• Asbestosis
• Mesothelioma
• Lung cancer

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Asbestos Removal
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Asbestos Exports

• 96 of asbestos mined in Canada is exported
• Canada is worlds second largest exporter of
  asbestos (Russia is 1)
• Exports primarily to developing countries such as
  India, Indonesia, Thailand

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Rotterdam Convention

• U.N. treaty to promote shared responsibilities
  related to importing hazardous chemicals
• Promotes prior informed consent and open exchange
  of information (proper labeling, directions on
  safe handling)
• Amphibole asbestos (Actinolite, Anthophyllite,
  Amosite, Crocidolite, Tremolite) covered under
  the convention
• Chrysotile asbestos not covered

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Canadas Position

• Chrysotile asbestos is a less potent carcinogen
  than amphibole asbestos
• Asbestos need not be dangerous if used safely
• Formally opposes addition of chrysotile to
  Rotterdam Convention

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Woman sifting asbestos into powder, Bangladesh
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Canadas Ugly Secret

• CBC The National
• June 10, 2009
• Mellissa Fung
• Cbc.ca/national
• Next day discussed in Parliament
• (see Asbestos concerns follow-up)

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Moral Question

• Is it right to export a product that we consider
  unsafe for domestic use?